How get stateUpdate by accountBlock?

[fishTsai20]

var ab tlb.AccountBlock
if err = tlb.LoadFromCell(&ab, slc); err != nil {
return fmt.Errorf("faled to parse account block: %w", err)
}
addr := address.NewAddress(0, byte(0), ab.Addr)
log.Info("account block's ", zap.Any("address", addr))
//state_update:^(HASH_UPDATE Account)
update := ab.StateUpdate.BeginParse()
var stateUpdate tlb.HashUpdate
err = tlb.LoadFromCell(&stateUpdate, update)
if err != nil {
log.Error("failed to get stateUpdate of account", zap.Any("address", addr), zap.Error(err))
return err
}

failed to get stateUpdate of account {"address": "EQAzMzMzMzMzMzMzMzMzMzMzMzMzMzMzMzMzMzMzMzMzM7SN", "error": "magic is not correct for tlb.HashUpdate, want #72"}

[xssnick]

Hi, it looks like a different data inside ab.StateUpdate, you can do println(ab.StateUpdate.Dump()) to check, maybe it is pruned (collapsed part of merkle proof)

[fishTsai20]

9[500_] -> { 700[7333333333333333333333333333333333333333333333333333333333333333300002C285E7463C1848974E46DC8A97C4504891082FC0CA7C3BAACF53246573BA115992C293DEE8400002C285E65218266C31A96000140_] -> { 2[0_], 520[72EEA4BB9B1F6083C49D08F503E9DCBFF278E79253AF02972D54674716F85D8ADAD2CB747F6C5D680946ADE5E14E054E1140F676ACADF3051F98BE0AA11520861D], 21[203020] -> { 640[43281010B0760000000000000000009600000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000], 365[C00000000000000000000000012D452DA449E50B8CF7DD27861F146122AFE1B546BB8B70FC8216F0C614139F8E00] } } }
Didn't see any Pruned Branch Cell.
Isn't your type definition consistent with TON's?
https://github.com/ton-blockchain/ton/blob/24dc184a2ea67f9c47042b4104bbb4d82289fac1/crypto/block/block.tlb#L231-L233
How do I parse this StateUpdate ?